When most people think of mussels, what immediately comes to mind might be a savory seafood dish or favorite seafood restaurant. But to Dr. Alireza Moshaverinia and his team of researchers at the UCLA School of Dentistry, it’s the ability that mussels have to stick to wet surfaces that is of particular interest.
Partially inspired by this concept and with support from CIRM, the team of researchers developed the first adhesive hydrogel specifically to regenerate bone and tissue defects following head and neck injuries.
Over the past few years, surgeons and clinicians have began to use hydrogels to administer stem cells to help regenerate lost tissues and for bone defects. Hydrogels are beneficial because they can be effective at carrying stem cells to targeted areas inside the body. However, when used in surgeries of the mouth, they tend to become less effective because blood and saliva prevent them from properly adhering to the targeted site. As a result of this, the stem cells don’t stay in place long enough to deliver their regenerative properties.
To help with this problem, the researchers at UCLA developed a new hydrogel by adding alginate into the mix. Alginates are found in the cells of algae and form a sticky, gum-like substance when wet.
The scientists then tested their new hydrogel by loading it with bone building stem cells and applying it to the mouths of rats with an infectious disease that affects the bone structure. They then sealed the hydrogel in place and applied a light treatment, similar to what dentists use in humans to solidify dental fillings.
The results showed that the bone around the implants in all of the rats had completely regenerated.
In a news release from UCLA, Dr. Moshaverinia elaborates on what this study means for potential future treatments.
“The light treatment helped harden the hydrogel, providing a more stable vehicle for delivery of the stem cells. We believe that our new tissue engineering application could be an optimal option for patients who have lost their hard and soft craniofacial tissues due to trauma, infection or tumors.”
The full study was published in Science Translational Medicine.
Snake venom can be deadly without proper treatment. Interestingly enough, it may also hold the key for treatments against pain, high blood pressure, and cancer according to one analysis. Despite this, scientists still do not understand much about the biology behind the wide range of different snake venoms, which can make it challenging to develop effective treatments in the event of snake bites.
Fortunately, a new study by Dr. Hans Clevers and his team at the Hubrecht Institute in the Netherlands could significantly aid the understanding of snake venom. Dr. Clevers and his team were able to grow miniature snake venom glands using snake stem cells. What’s more remarkable is that these “mini-organs” produced real venom!
In an article posted in Science Magazine, Dr. Clevers talks about how his study was navigating uncharted waters.
“Nobody knew anything about stem cells in snakes. We didn’t know if it was possible at all.”
To produce these “mini-organs”, the researchers removed the stem cells from the venom glands of nine different types of snake and placed them in a mixture of growth factors that contained different hormones and proteins. It turns out that the snake stem cells responded to the same factors used on human and mouse stem cells.
Eventually, the stem cells grew into little clumps of tissue and when the researchers removed the growth factors, they started to change into the same kind of cells that produce venom in the glands of snakes. Additionally, they were able to find that these “mini-organs” expressed similar genes as those observed in real venom glands.
The scientists were even able to test the nature of the “mini-organ” venom as well. A chemical and genetic analysis of the venom revealed that it matched the one made by real snakes. After testing this venom on mouse muscle cells and rat neurons, they also found that it damaged these cells similar to real venom.
The type of toxins and concentration levels can vary drastically in snake venom, even within the same species. This can make developing treatments challenging since they can only be used to combat one type of venom.
Dr. Clevers and his team now plan to study the complexities of venom and venom glands by compiling a “biobank” of frozen organoids from venomous reptiles around the world that could help researchers find broader treatments. With the aid of their newly developed “mini-organs”, all of this can be done without the handling of live, dangerous snakes, some of which are rare and difficult to keep in captivity.
Zika virus is caused by a virus transmitted by Aedes mosquitoes. People usually develop mild symptoms that include fever, rash, and muscle and joint pain. However, Zika virus infection during pregnancy can lead to much more serious problems. The virus causes infants to be born with microcephaly, a condition in which the brain does not develop properly, resulting in an abnormally small head. In 2015-2016, the rapid spread of the virus was observed in Latin America and the Caribbean, increasing the urgency of understanding how the virus affected brain development.
Working independently, Dr. Tariq Rana and Dr. Jeremy Rich from UC San Diego identified the same molecule, αvβ5 integrin, as the Zika virus’ key to entering brain stem cells. The two studies, with the aid of CIRM funding, discovered how to take advantage of the molecule in order to block the Zika virus from infecting cells. In addition to this, they were able to turn it into something useful: a way to destroy brain cancer stem cells.
In the first study, Dr. Rana and his team used CRISPR gene editing on brain cancer stem cells to delete individual genes, which was done to see which genes are required for the Zika virus to enter the cells. They discovered that the gene responsible for αvβ5 integrin also enabled the Zika virus.
In a press release by UC San Diego, Dr. Rana elaborates on the importance of his findings.
“…we found Zika uses αvβ5, which is unique. When we further examined αvβ5 expression in brain, it made perfect sense because αvβ5 is the only integrin member enriched in neural stem cells, which Zika preferentially infects. Therefore, we believe that αvβ5 is the key contributor to Zika’s ability to infect brain cells.”
In the second study, Dr. Rich and his team use an antibody to block αvβ5 integrin and found that it prevented the virus from infecting brain cancer stem cells and normal brain stem cells. The team then went on to block αvβ5 integrin in a mouse model for glioblastoma, an aggressive type of brain tumor, by using an antibody or deactivating the gene responsible for the molecule. Both approaches blocked Zika virus infection and allowed the treated mice to live longer than untreated mice.
Dr. Rich then partnered with Dr. Alysson Muotri at UC San Diego to transplant glioblastoma tumors into laboratory “mini-brains” that can be used for drug discovery. The researchers discovered that Zika virus selectively eliminates glioblastoma stem cells from the mini-brains. Additionally, blocking αvβ5 integrin reversed that anti-cancer activity, further demonstrating the molecule’s crucial role in Zika virus’ ability to destroy cells.
In the same UC San Diego press release, Dr. Rich talks about how understanding Zika virus could help in treating glioblastoma.
“While we would likely need to modify the normal Zika virus to make it safer to treat brain tumors, we may also be able to take advantage of the mechanisms the virus uses to destroy cells to improve the way we treat glioblastoma.”
Dr. Rana’s full study was published in Cell Reports and Dr. Rich’s full study was published in Cell Stem Cell.
While we are here at ISSCR 2019 hearing various scientists talk about their work, we realize that there are various breakthroughs in stem cell research in a wide variety of different fields going on every day. It is wonderful to see how scientists are hard at work in developing the latest science and pushing innovation. Here are two remarkable stories you may have missed this week.
Scientists developing way to help premature babies breathe easier
Researchers at Cincinnati Children’s Hospital Medical Center are looking at ways to stimulate lung development in premature infants who suffer from a rare condition called Bronchopulmonary Dysplasia (BPD), which can cause lifelong breathing problems and even death. Using a mouse model of BPD, extensive analysis, and testing, the scientists were able to create a proposal to develop a stem cell therapy based on what are called c-KIT endothelial progenitor cells.
Premature babies, unable to breathe on their own, rely on machines to help them breathe. Unfortunately, these machines can interfere with lung development as well. The cells proposed in the stem cell therapy are common in the lungs of infants still in the womb and help in the formation of capillaries and air sacs in the lungs called alveoli.
In a press release, Dr. Vlad Kalinichenko, lead investigator for this work, was quoted as saying,
“The cells are highly sensitive to injury by high oxygen concentrations, so lung development in premature babies on mechanical oxygen assistance is impeded. Our findings suggest using c-KIT-positive endothelial cells from donors, or generating them with pluripotent stem cells, might be a way to treat BPD or other pediatric lung disorders associated with loss of alveoli and pulmonary microvasculature.”
The full results were published in American Journal of Respiratory and Critical Care Medicine.
Mice with a human immune system help research into cancer and infections
Speaking of a mouse model, researchers from Aarhus University and Aarhus University Hospital have succeeded in using mice with a transplanted human immune system to study functions in the immune system which are otherwise particularly difficult to study. This work could open the possibilities towards looking further into disease areas such as cancer, HIV, and autoimmune diseases.
Before potential treatments can be tested in humans, there needs to be extensive animal testing and data generated. However, when the disease relate’s to the human immune system, it can be particularly challenging to evaluate this in mice. The research team succeeded in transplanting human stem cells into mice whose own immune system is disabled, and then triggered a type of reaction in the immune system which normally reacts to meeting a range of viruses and bacteria.
In a press release, Dr. Anna Halling Folkmar, one of the researchers behind the study, says that,
“The humanised mice are an important tool in understanding how human immune cells behave during diseases and how they react to different medical treatments.”
When most people think of stem cells, they might conjure up an image of small dots under a microscope. It is hard to imagine these small specs being applied to three-dimensional structures. But like a pointillism painting, such as A Sunday Afternoon on the Island of La Grande Jatte by Georges-Pierre Seurat, stem cells can be used to help build things never thought possible. Two studies demonstrate this concept in very different ways.
A study at MIT used nanofiber coated with muscle stem cells and mesenchymal stem cells in an effort to provide a flexible range of motion for these stem cells. Hundreds of thousands of nanofibers were twisted, resembling yarn and rope, in order to mimic the pattern found in tendons and muscle tissue throughout the body. The researchers at MIT found that the yarn like structure of the nanofibers keep the stem cells alive and growing, even as the team stretched and bent the fibers multiple times.
Normally, when a person injures these types of tissues, particularly around a major joint such as the shoulder or knee, it require surgery and weeks of limited mobility to heal properly. The MIT team hopes that their technology could be applied toward treating the site of injury while maintaining range of motion as the newly applied stem cells continue to grow to replace the injured tissue.
In an article, Dr. Ming Guo, assistant professor of mechanical engineering at MIT and one of the authors of the study, was quoted as saying,
“When you repair muscle or tendon, you really have to fix their movement for a period of time, by wearing a boot, for example. With this nanofiber yarn, the hope is, you won’t have to wearing anything like that.”
Their complete findings were published in the Proceedings of the National Academy of Sciences (PNAS).
In a separate study, researchers in Germany have successfully created transparent human organs, paving the way to print three-dimensional body parts. Dr. Ali Erturk at Ludwig Maximilians University in Munich, with a team of scientists, developed a technique to create a detailed blueprint of organs, including blood vessels and every single cell in its specific location. These directions were then used to print a scaffold of the organ. With the help of a 3D printer, stem cells, acting like ink in a printer, were injected into the correct positions to make the organ functional.
Previously, 3D-printed organs lacked detailed cellular structures because they were based on crude images from computer tomography or MRI machines. This technology has now changed that.
“We can see where every single cell is located in transparent human organs. And then we can actually replicate exactly the same, using 3D bioprinting technology to make a real functional organ. Therefore, I believe we are much closer to a real human organ for the first time now.”
governing Board of the California Institute for Regenerative Medicine (CIRM)
awarded $3.9 million to Ankasa Regenerative Therapeutics for a promising approach to treat a
degenerative condition that can cause chronic, progressive back pain.
As we get
older, the bones, joints and ligaments in our back become weak and less able to
hold the spinal column in alignment. As
a result, an individual vertebral bone in our spine may slip forward over the
one below it, compressing the nerves in the spine, and causing lower back pain
or radiating pain. This condition,
called degenerative spondylolisthesis, primarily affects individuals over the
age of 50 and, if left untreated, can cause intense pain and further
degeneration of adjacent regions of the spine.
treatment usually involves taking bone from one of the patient’s other bones,
and moving it to the site of the injury.
The transplanted bone contains stem cells necessary to generate new
bone. However, there is a caveat to this
approach— as we get older the grafts become less effective because the stem
cells in our bones are less efficient at making new bone. The end result is little or no bone
Ankasa has developed ART352-L, a protein-based drug product
meant to enhance the bone healing properties of these bone grafts. ART352-L works by stimulating bone stem cells
to increase the amount of bone produced
by the graft.
The award is in the form of a CLIN1 grant, with the goal of
completing the testing needed to apply to the Food and Drug Administration
(FDA) for permission to start a clinical trial in people.
This is a project that CIRM has supported through earlier
phases of research.
“We are excited to see the development that this approach has made since its early stages and reflects our commitment to supporting the most promising science and helping it advance to the clinic,” says Maria T. Millan, MD, President & CEO of CIRM. “There is an unmet medical need in older patients with bone disorders such as degenerative spondylolisthesis. As our population ages, it is important for us to invest in potential treatments such as these that can help alleviate a debilitating condition that predisposes to additional and fatal medical complications.”
See the animated video below for a descriptive and visual synopsis of degenerative spondylolisthesis.
Some of you might remember a movie in the early 2000s by the name of “Miracle in Lane 2”. The film is based on an inspirational true story and revolves around a boy named Justin Yoder entering a soapbox derby competition. In the movie, Justin achieves success as a soapbox derby driver while adapting to the challenges of being in a wheelchair.
The reason that Justin is unable to walk is due to a birth defect known as spina bifida, which causes an incomplete closing of the backbone portion of the spinal cord, exposing tissue and nerves. In addition to difficulties with walking, other problems associated with this condition are problems with bladder or bowel control and accumulation of fluid in the brain.
According to the Center for Disease Control (CDC) , each year about 1,645 babies in the US are born with spina bifida, with Hispanic women having the highest rate of children born with the condition. There is currently no cure for this condition, but researchers at UC Davis are one step closer to changing that.
Dr. Aijun Wang, Dr. Diana Farmer, and their research team have identified crucial byproducts produced by stem cells that play an important role in protecting neurons. These byproducts could assist with improving lower-limb motion in patients with spina bifida.
Prior to this discovery, Dr. Farmer and Dr. Wang demonstrated that prenatal surgery combined with connective tissue (e.g. stromal cells) derived from stem cells improved hind limb control in dogs with spina bifida. Below you can see a clip of two English bulldogs with spina bifida who are now able to walk.
Pursuing an education can be quite the challenge in itself without the added pressure of external factors. For Brenden Whittaker, a 25 year old from Ohio, the constant trips to the hospital and debilitating nature of an inherited genetic disease made this goal particularly challenging and, for most of his life, out of sight.
Brenden was born with chronic granulomatous disease (CGD), a rare genetic disorder that affects the proper function of neutrophils, a type of white blood cell that is an essential part of the body’s immune system. This leads to recurring bacterial and fungal infections and the formation of granulomas, which are clumps of infected tissue that arise as the body attempts to isolate infections it cannot combat. People with CGD are often hospitalized routinely and the granulomas themselves can obstruct digestive pathways and other pathways in the body. Antibiotics are used in an attempt to prevent infections from occurring, but eventually patients stop responding to them. One in two people with CGD do not live past the age of 40.
In Brenden’s case, when the antibiotics he relied on started failing, the doctors had to resort to surgery to cut out an infected lobe of his liver and half his right lung. Although the surgery was successful, it would only be a matter of time before a vital organ was infected and surgery would no longer be an option.
It’s been a little over three years since Brenden received this treatment in late 2015, and the results have been remarkable. Dr. David Williams, Brenden’s treating physician, expected Brenden’s body to produce at least 10 percent of the functional neutrophils, enough so that Brenden’s immune system would provide protection similar to somebody without CGD. The results were over 50 percent, greatly exceeding expectations.
In an article published by The Harvard Gazette, Becky Whittaker, Brendan’s mother, is quoted as saying, ““Each day that he’s free of infection, he’s able to go to class, he’s able to work at his part-time job, he’s able to mess around playing with the dog or hanging out with friends…[this] is a day I truly don’t believe he would have had beyond 2015 had something not been done.”
In addition to the changes to his immune system, the gene therapy has reinvigorated Brenden’s drive for the future. Living with CGD had caused Brenden to miss out on much of his schooling throughout the years, having to take constant pauses from his academics at a community college. Now, Brenden aims to graduate with an associate’s degree in health sciences in the spring and transfer to Ohio State in the fall for a bachelor’s degree program. In addition to this, Brenden now has dreams of attending medical school.
In The Harvard Gazette article, Brenden elaborates on why he wants to go to medical school saying, ” Just being the patient for so long, I want to give back. There are so many people who’ve been there for me — doctors, nurses who’ve been there for me [and] helped me for so long.”
In a press release dated February 25, 2019, Orchard Therapeutics, a biopharmaceutical company that is continuing the aforementioned approach for CGD, announced that six patients treated have shown adequate neutrophil function 12 months post treatment. Furthermore, these six patients no longer receive antibiotics related to CGD. Orchard Therapeutics also announced that they are in the process of designing a registrational trial for CGD.
Blood is the lifeline of the body. The continuous, unimpeded circulation of blood maintains oxygen flow throughout the body and enables us to carry out our everyday activities. Unfortunately, there are individuals whose own bodies are in a constant battle that prevents this from occurring seamlessly. They have something known as sickle cell disease (SCD), an inherited condition caused by a mutation in a single gene. Rather than producing normal, circular red blood cells, their bodies produce sickle shaped cells (hence the name) that can become lodged in blood vessels, preventing blood flow. The lack of blood flow can cause agonizing pain, known as crises, as well as strokes. Chronic crises can cause organ damage, which can eventually lead to organ failure. Additionally, since the misshapen cells don’t survive long in the body, people with SCD have a greater risk of being severely anemic and are more prone to infections. Monthly blood transfusions are often needed to help temporarily alleviate symptoms. Due to the debilitating nature of SCD, important aspects of everyday life such as employment and health insurance can be extremely challenging to find and maintain.
An estimated 100,000 people in the United States are living with SCD. Around the world, about 300,000 infants are born with the condition each year, a statistic that will increase to 400,000 by 2050 according to one study. Many people with SCD do not live past the age of 50. It is most prevalent in individuals with sub-Saharan African descent followed by people of Hispanic descent. Experts have stated that advances in treatment have been limited in part because SCD is concentrated in poorer minority communities.
Despite these grim statistics and prognosis, there is hope.
The New York Times and Boston Herald recently released featured articles that tell the personal stories of patients enrolled in a clinical trial conducted by bluebird bio. The trial uses gene therapy in combination with hematopoietic (blood) stem cells (HSCs) to give rise to normal red blood cells in SCD patients.
Here are the stories of these patients. To read the full New York Times article, click here. For the Boston Herald article, click here.
Emmanuel “Manny” Johnson was the very first patient in the SCD trial. He was motivated to participate in the trial not just for himself but for his younger brother Aiden Johnson, who was also born with SCD. Manny has a tattoo with Aiden’s name written inside a red sickle cell awareness ribbon.
In the article Manny is quoted as saying “It’s not only that we share the same blood disease, it’s like I have to do better for him.”
Since receiving the treatment, Manny’s SCD symptoms have disappeared.
For Brandon Williams of Chicago, the story of SCD is a very personal one. At just 21 years old, Brandon had suffered four strokes by the time he turned 18. His older sister, Britney Williams, died of sickle cell disease at the age of 22. Brandon was devastated and felt that his own life could end at any moment. He was then told about the SCD trial and decided to enroll. Following the treatment, his symptoms have vanished along with the pain and fear inflicted by the disease.
The NY Times piece also profiles Carmen Duncan, a 20 year old from Charleston, South Carolina. She had her spleen removed when she was just two years old as a result of complications form SCD. Duncan spent a large portion of her childhood in hospitals, coping with the pain in her arms and legs from blocked blood vessels. She enrolled in the SCD trial as well and she no longer has any signs of SCD. Duncan had aspirations to join the military but was unable to because of her condition. Now that she is symptom free, she plans to enlist.
A new study published in STEM CELLS, conducted by researchers at the University of Amsterdam, shows how mesenchymal stem cells (MSCs) can restore the health and improve the function of the immune system, which could benefit the treatment of sepsis. Sepsis is a life-threatening complication from an infection that can lead to multiple organ failure. It is a major cause of illness and death worldwide and despite the use of antibiotics it kills about one in every four patients who contract it.
Since early studies done on animals have shown that treating sepsis with MSCs can reduce the mortality rate by as much as 73 percent, a group of researchers from University of Amsterdam sought to answer this question: could humans realize the same benefits?
So, the team conducted an experiment by taking a group of healthy volunteers and inducing endotoxemia in them, where bacterial toxins can build up and cause fever, nausea and vomiting but do not cause long-term harm to the participants (?). The idea was that by inducing endotoxemia, which exhibits some of the key characteristics of sepsis, that they could model the condition in people.
One hour prior to the initial dose, each person was given an infusion of either adipose (fat) mesenchymal stem cells (ACSs) taken from a donor, or a placebo as a control. Those receiving the ASCs were divided into three groups, with each group receiving a consecutively higher dose of cells.
In a news release, Desiree Perlee, senior author of the study, said the study provided some valuable insights and information:
“The results showed that the ASCs were well tolerated…We realize that there is a limitation with the endotoxemia model. Although in a qualitative way it resembles responses seen in patients with sepsis, it differs in that sepsis-associated alterations are more severe and sustained, while in the endotoxemia model responses occur in a very rapid, short-lived and transient way. But despite these limitations, some of our findings confirm the earlier studies on animals. We believe they show further testing of ASCs in actual sepsis patients is warranted.”
Dr. Jan Nolta, Editor-in-Chief of STEM CELLS (and a CIRM-grantee), said, “This novel clinical trial provides important insight into the mechanism of action of MSCs in inflammation and provides human safety data in support of treatment of sepsis using MSCs.